Doron Lemze (JHU) : Dark Matter Velocity Anisotropy in Galaxy Clusters

Out of the dark matter (DM) full space-phase density, the DM mass distribution was until recently the only cluster property that could be inferred from simulations and tested against observational data. The DM velocity space is also important since it gives us information about DM particle features. I'll show first indirect estimations for the DM velocity anisotropy in clusters. Then I'll compare them to the expected profile from a sample of some 6000 cluster-size halos (at redshift zero) identified in a Lambda CDM hydrodynamical adaptive mesh refinement simulation done with the Enzo code. I'll speculate what can cause for differences between the estimated and expected values. Finally, I'll present work in progress that will give a clearer answer regarding the size of these differences.